Oxygen concentrator



FIG. 1 is a front elevation view of an oxygen concentrator showing thenew design;

FIG. 2 is a back elevation view thereof;

FIG. 3 is a left-side view thereof;

FIG. 4 is a right-side view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a perspective view thereof; and,

FIG. 8 is another perspective view thereof.

The broken lines depict portions of the article that form no part of theclaimed design.

CLAIM The ornamental design for an oxygen concentrator, as shown anddescribed.